Anti-syphon device



FIG. 1 is a perspective view of an anti-syphon device according to an embodiment of the invention.

FIG. 2 is a front elevational view of an anti-syphon device according to an embodiment of the invention.

FIG. 3 is a rear elevational view of an anti-syphon device according to an embodiment of the invention.

FIG. 4 is a top plan view of an anti-syphon device according to an embodiment of the invention; and,

FIG. 5 is a bottom plan view of an anti-syphon device according to an embodiment of the invention.

Items shown in broken lines are for illustrative purposes only and form no part of the claimed design. 

I claim the ornamental design for an anti-syphon device, as shown and described. 